Elevated vacuum suspension preserves residual-limb skin health in people with lower-limb amputation: Randomized clinical trial

Abstract

Abstract-A growing number of clinical trials and case reports support qualitative claims that use of an elevated vacuum suspension (EVS) prosthesis improves residual-limb health on the basis of self-reported questionnaires, clinical outcomes scales, and wound closure studies. Here, we report first efforts to quantitatively assess residual-limb circulation in response to EVS. Residual-limb skin health and perfusion of people with lower-limb amputation (N = 10) were assessed during a randomized crossover study comparing EVS with nonelevated vacuum suspension (control) over a 32 wk period using noninvasive probes (transepidermal water loss, laser speckle imaging, transcutaneous oxygen measurement) and functional hyperspectral imaging approaches. Regardless of the suspension system, prosthesis donning decreased perfusion in the residual limb under resting conditions. After 16 wk of use, EVS improved residual-limb oxygenation during treadmill walking. Likewise, prosthesis-induced reactive hyperemia was attenuated with EVS following 16 wk of use. Skin barrier function was preserved with EVS but disrupted after control socket use. Taken together, outcomes suggest chronic EVS use improves perfusion and preserves skin barrier function in people with lower-limb amputation.Clinical Trial Registration: ClinicalTrials.gov; "Evaluation of limb health associated with a prosthetic vacuum socket system": NCT01839123; https://clinicaltrials.gov/ct2/show/ NCT01839123?term=NCT01839123&rank=1

Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health

“…4 The study did not account for movement at the interface, mostly because there was not a method to quantify these data at the time of the study. The traditional teaching from Orthotic and Prosthetic educational programs is that motion should be eliminated between the residual limb and socket, although this is generally determined by visually inspecting the socket as the user ambulates.…”

“…Therefore, if a relatively similar level of suspension is generated at a lower vacuum setting, is there a need to draw the highest possible vacuum pressure of the pump? How did differences in vacuum pressure setting, and therefore amount of motion between the limb and socket, impact the results of the previous limb health study 4 ? Should all motion totally be eliminated, or is there a threshold of movement that is optimal for the health of the limb and/or user comfort?…”

“…3 The beneficial changes in skin health and circulation of the limb resulting from the use of EVS have recently been objectively quantified using a series of novel approaches. 4 Data from a microprocessor-controlled EVS may provide an appropriate measurement of socket fit. EVS creates subatmospheric pressure between the prosthetic socket and liner worn over the residual limb.…”

Standardized Approach to Quantitatively Measure Residual Limb Skin Health in Individuals with Lower Limb Amputation

“…[18][19][20] We recently reported on the beneficial effects of elevated vacuum suspension as they relate to residual limb health in TT and TF subjects. 21 In light of the small sample size employed in the current study, outcomes were not stratified according to suspension type. Future efforts will be focused to investigate the relationship between suspension type and residual limb skin health.…”

Residual Limb Health and Prosthetics

“…The LimbLogic ® vacuum system developed as a result of a Veterans Affairs (VA) grant funded collaborative work with Ohio Willow Wood was commercialized for clinically relevant quantification of prosthetic socket performance. Elevated vacuum suspension (EVS) [20,21] (Figure 3) creates subatmospheric pressure between the prosthetic socket and liner worn over the residual limb. Studies performed with this system identified that variances among individuals may be a result of different gait styles, tissue types, residual limb geometries, prosthesis weight distribution, and socket fit.…”